Eight Tanzanian police officers have been charged with murder over the shooting of four men last month.
President Jakaya Kikwete was praised for acting quickly to order the arrests
The police originally said the four were suspected armed robbers but an official investigation found they were gemstone dealers.
Police are looking for the remaining seven members of the team involved in the shooting.
The men were shot just days after the launch of a "shoot-to-kill" policy following a spate of armed robberies.
There were tearful scenes outside court as the eight men were charged.
Relatives praised President Jakaya Kikwete for acting quickly on the report of a commission he had set up to investigate the shooting in the central region of Morogoro and ordering the policemens' arrest.
They said previous such reports had been left to gather dust in cupboards.
The BBC's John Ngahyoma in Dar es Salaam says the shooting caused a public uproar, leading to the inquiry.
At the time of the shooting, acting regional police commander Abdallah Zombe told the BBC: "We kill notorious robbers, not innocent people."
The police accused the men of robbing a jewellery shop and engaging them in a shoot-out.
But the inquiry found no evidence there had been a shoot-out.